Couplings for drill rods



y 1962 R. T. WOODINGS 3,032,360

COUPLING FOR DRILL RODS Filed May 14, 1959 INVENTOR. Robert TWoodings BYM. 61mm 'Q M ATTORNEY S United States Patent Office 3,032,360 PatentedMay 1, 1932 3,032,360 COUPLINGS FOR DRILL RODS Robert T. Woodings, 1214Anderson Road, Pittsburgh, Pa. Filed May 14, 1959, Ser. No. 813,170 3Claims. (Cl. 287-108) This invention relates to couplings for drill rodsand, particularly, a coupling adapted for making up long lengths ofdrill rod during the drilling operation.

The drilling of holes through rock in preparing for blasting operationsin a quarry frequently require a depth of hole which may be 50 or 60feet deep. To provide the required length of drill rod, the rod is madeup of a plurality of sections of rod which are customarily to 15 feetlong. The coupling of the invention is for the purpose of readilysecuring these sections together.

During the drilling operation the bit or drilling tool is suspended fromthe rig, which is a suitable mechanism mounted above ground for raising,dropping and rotating the bit in cutting the required depth of hole tobe drilled. The drill rod connects the bit with a rig and, therefore, iscontinuously subjected to impact and torsional stresses throughout thedrilling operation. Obviously, these stresses upon the drill rod and itscouplings are increased as the depth of drilled hole is increased.

The drill rod sections are customarily hexagonal in cross-section, butoccasionally a rod of circular crosssection is used. The couplingcustomarily connecting adjacent ends of the rod sections must be readilyattachable and must readily transmit both compressive and torsionalstresses between the rod sections. One object of the invention is toprovide a sectional coupling which may be readily applied to the drillrod sections and prevent relative movement between adjacent ends of therod sections connected thereby, or breaking of the rods at the coupling.

Another object of the invention is to provide a coupling of thecharacter described which is readily applied and is not subject todistortion during use, so as to be readily removed after the drillingoperation is completed.

These and other objects of the invention will be made apparent from thefollowing description and the drawing forming a part thereof wherein:

FIG. 1 shows a longitudinal view, partly in cross-section, of theassembled coupling and adjacent ends of the hexagonal drill rodsections;

FIG. 2 shows a vertical cross-section through the as sembled couplingtaken on lines II-II of FIG. 1;

FIG. 3 shows an end elevation of the assembled rod and coupling taken onlines IIIIII of FIG. 1;

FIG. 4 shows a view similar to FIG. 1 illustrating a modified form ofthe invention; and

FIG. 5 shows a section taken on lines V-V of FIG. 4.

Referring now to the drawings and particularly FIGS. 1 to 3, the drillrod sections 1 are hexagonal in crosssection and have the adjacentabutting ends 2 thereof shaped to provide an adequate bearing surfacefor one rod upon the other. Preferably, the center of each drill rod endis recessed, as at 3. Inwardly from each end of the drill rod section isan enlarged portion or collar 4, which is preferably circular incross-section but may be of other desired shapes. Each drill rod sectionis preferably provided with an axially extending opening 5 for a wellknown purpose.

The coupling is comprised of two half sections 6 and a slidable clampingsleeve 7. The sections 6 are each less than one half a circle, so thatwhen assembled, about rods 1, provide a space 8 between their meetingedges. Each section 6 of FIG. 1, has a semi-circular outer periphery 9and an internal longitudinally extending cavity 10 receivingsubstantially one half the periphery of the hexagonal drill rod 1.Intermediate the ends of each clamp section 6 are two spacedsemi-circular recesses 11 preferably spaced equal distances about themid-portion of the section. Each recess 11 has a radius of not less thanone-half the maximum cross-sectional dimension of the hexagonal drillrod 1 received in the cavity 10 and of the collar 4 on said rod. Thetransverse width of each recess 11 is greater than the thickness of therod collars 4 so as to freely receive same. Preferably the spacing ofthe recesses 11 are such that the abutting ends of the drill rods 1received in each section 6 has the face 4a of each rod collar 4, remotefrom the adjacent end of the drill rod, engaging the adjacent face ofthe clamp recess 11 so that the drill rod end absorbs and transmits allcompression shock from the bit and the coupling receives only tensionand torsional stresses. The coupling sections 6 are retained inassembled clamping arrangement about the ends of the coupling rodstherein by means of the sleeve 7. The coupling sleeve 7 is a hollowcylindrical member of a length less than that of the coupling halves 6.The outer periphery of the coupling sections are provided with aperipheral taper from end to end, and the inner periphery of sleeve 7 istapered so as to lock upon the sections 6 when forced longitudinallythereof.

Referring now to FIGS. 4 and 5 of the drawings, wherein is shown amodification of the coupling of the invention for use with round insteadof hexagonal drill rods, the coupling is again comprised of sections 106and a sleeve 107. Each end of each round drill rod section 101 isprovided with an abutting end portion 102, axially extending opening andend recess 103 as in FIG. 1. Each rod 101 is also provided with anenlarged collar portion 104 received in recesses 111, as in FIG. 1.Additionally each drill rod 101 inwardly of collar 104 is pro vided withcircumferentially spaced projecting portions 112 which are preferablyspaced about the periphery of rod 101. These portions 112 have across-sectional area sufiicient to resist shearing under maximumtorsional stresses imposed upon the rod 101. The coupling sections 106are each provided with longitudinally extending cavities 111 to receivethe rod 101 and recesses 111 to receive the collars 104 thereof in thesame relation as described in regard to FIG. 1. Each clamp section 106,within the cavity 110 thereof is provided with an additional recess 113,to receive one of the portions 112 of each rod 101 disposed therein.Since the rod portions 112 need to resist only torsional stresses, therecesses 113 may be made of suflicient size to freely receive portions112 and, therefore, may be of larger dimension. The width dimensionshould be sufficiently close fitting to prevent relative rotary movementbetween clamp and rod. The sleeve 107 is similar to sleeve 7 and retainsthe sections 106 in assembled relation.

The couplings of the invention are used to extend the length of thedrill rod as the depth of drilled hole increases. The fitted abuttingends of the drill rods, within the coupling, take up the major portionof the compressive shocks imposed upon the rod during the drillingoperation. The fit between the rod collars and recesses in the couplingprevent any substantial separation of the abutting rod ends therein andthus the coupling is subject to only tension when drill bit and rod areraised during the drilling operation. The angular relation of theperipheral faces of the drill rod and clamping engagement of thecoupling therewith prevent relative rotation between rod and couplingduring the drilling operation. Since the diameter of the drill bitexceeds the diameter of the coupling, the couplings moving within thedrilled hole are normally not damaged by frictional engagement with thewalls of the drilled opening.

I claim:

1. A coupling connection between adjacent ends of two sections of adrill rod suspending and rotating a drilling tool, comprising a pair ofhexagonally shaped drill rods each having shaped abutting end portions,an enlarged integral collar enclosing the periphery of each rod inwardlyof each said abutting end portions, a pair of members extendingcontinuously in longitudinal overlapping relation to both collars onsaid rod sections and having inner faces conforming to the periphery ofthe rod sections between and at opposite sides of said rod collars, eachsaid member having a tapering semi-cylindrical outer face disposedwholly to one side of the longitudinal center of the rods and in spacedrelation to the similar member on the opposite side of said longitudinalcenter of the rods, each said members having recessed portions on theirinner faces receiving said rod collars, each said recesses having thewidth and diameter thereof in excess of the width and diameter of therod collar received therein and spaced to embrace said collars to retainthe rod ends between them in abutting engagement, and a hollowcylindrical sleeve having a tapering inner periphery slidably receivedover said members to retain the members in clamping engagement with onlysaid rod end portions.

2. A coupling connection between adjacent ends of sections of a drillrod suspending and rotating a drilling tool, comprising a pair of rounddrill rods each having shaped abutting end portions, an annular collarformed on each drill rod section in inwardly spaced relation to saidshaped abutting end portion,- a plurality of circumferentially spacedlongitudinally disposed projections from each drill rod section spacedinwardly of each said rod collars, a longitudinally extending hollowcylindrical sleeve enclosing said rod ends, collars and projections,said sleeve comprising two half sections embracing less than one-halfthe periphery of said rods, each sleeve section having an inner cavityconforming to the adjacent surfaces of the drill rods and recesses insaid cavities receiving said rod collars and projections, and a tubularmember slidably received over said sleeve sections clamping them to saiddrill rods.

3. A coupling connection between adjacent ends of two sections of adrill rod suspendingand rotating a drilling 5 tool, comprising a pair ofdrill rod sections each having shaped abutting end portions, an enlargedintegral collar enclosing the periphery of each rod section inwardly ofeach said abutting end portions, means on at least a portion of eachsaid rod section adjacent said collars providing angularly-disposedperipheral surfaces, a pair of members extending continuously inlongitudinal overlapping relation to both collars and said means of saidrod sections and having inner faces substantially conforming to theperiphery of the rod sections between and at opposite sides of saidcollar and to the angularly-disposed peripheral surfaces of said means,each said members having a tapering semi-cylindrical outer face disposedWholly to one side of the longitudinal center of the rods and in spacedrelation to the similar member on the opposite side of said longitudinalcenter of the rods, each said members having recessed portions on theirinner faces receiving said rod collars, each said recessed portionshaving a width and diameter thereof in excess of the width and diameterof the rod collars received therein and spaced to embrace said collarsto retain the rod ends between them in abutting engagement, and a hollowcylindrical sleeve having a tapering inner periphery slidably receivedover said members clamping them to said drill rods.

References Cited in the file of this patent UNITED STATES PATENTS 85,465McKinney Dec. 29, 1868 519,454 Holland May 8, 1894 904,210 Minard Nov.17, 1908 1,667,485 MacDonald Apr. 24, 1928 2,067,271 Johnson et al. Jan.12, 1937 2,133,050 Simmons Oct. 11, 1938 2,249,162 Nielsen July 15, 1941

